68 



VERTEBRATES : MAMMALS. 



Fig. 61. 



American Beaver, C. canadensis, Kuhl. 



in the banks, 

 whither they 

 retire when 

 their houses 

 are attacked. 

 The general 

 color of the 

 beaver is a 

 uniform red- 

 dish - brown, 

 and the fur 

 is of the best 

 quality, and 

 was former- 



ly very valuable. Only two species are known. 



The American Beaver, C. canadensis, Kuhl., found all 

 over North America ; and the European Beaver, C. fiber, 

 Linn., of the Old World. These are much alike. 



The Genus Castoroidcs comprises the Fossil Beaver, C. 

 ohioensis, Foster, of New York and westward, known only 

 from its skull, which shows that this beaver-like Rodent 

 was six times the bulk of our living species. 



The Genus Myopotamus comprises the Couia, M. coi- 

 pus, Cuv., of South America, which resembles the beaver 

 in size and habits, but has the tail round and long. The 

 fur is yellowish-gray, and is known among the hatters 

 under the name of nutria. 



The Genus Aplodontia comprises the Sewellel, A. lepo- 

 rina, Rich., of Puget's Sound, which is about the size and 

 general appearance of the muskrat, but with the tail very 

 short and much depressed. 



SACCOMYID/E, OR POUCHED GOPHER FAMILY.- -This 

 Family comprises Rodents which have large and distinct 

 external cheek-pouches, pelage composed of stiff hairs 

 with no under fur, molars ^, and the upper lip not cleft. 



